Commit 15235902 authored by Tamir Duberstein's avatar Tamir Duberstein Committed by Miguel Ojeda
Browse files

rust: kernel: use `core::ffi::CStr` method names 

Prepare for `core::ffi::CStr` taking the place of `kernel::str::CStr` by
avoiding methods that only exist on the latter.

Also avoid `Deref<Target=BStr> for CStr` as that impl doesn't exist on
`core::ffi::CStr`.

Link: https://github.com/Rust-for-Linux/linux/issues/1075


Signed-off-by: default avatarTamir Duberstein <tamird@gmail.com>
Reviewed-by: default avatarBenno Lossin <lossin@kernel.org>
Reviewed-by: default avatarAlice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250704-core-cstr-prepare-v1-6-a91524037783@gmail.com


[ Reworded title. - Miguel ]
Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent 10a7108d

rust/kernel/error.rs

+1 −1
Original line number Diff line number Diff line
@@ -188,7 +188,7 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { 
            Some(name) => f

                .debug_tuple(

                    // SAFETY: These strings are ASCII-only.

                    unsafe { core::str::from_utf8_unchecked(name) },

                    unsafe { core::str::from_utf8_unchecked(name.to_bytes()) },

                )

                .finish(),

        }

rust/kernel/str.rs

+10 −10
Original line number Diff line number Diff line
@@ -57,11 +57,11 @@ impl fmt::Display for BStr { 
    /// # use kernel::{prelude::fmt, b_str, str::{BStr, CString}};

    /// let ascii = b_str!("Hello, BStr!");

    /// let s = CString::try_from_fmt(fmt!("{ascii}"))?;

    /// assert_eq!(s.as_bytes(), "Hello, BStr!".as_bytes());

    /// assert_eq!(s.to_bytes(), "Hello, BStr!".as_bytes());

    ///

    /// let non_ascii = b_str!("🦀");

    /// let s = CString::try_from_fmt(fmt!("{non_ascii}"))?;

    /// assert_eq!(s.as_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());

    /// assert_eq!(s.to_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());

    /// # Ok::<(), kernel::error::Error>(())

    /// ```

    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -89,11 +89,11 @@ impl fmt::Debug for BStr { 
    /// // Embedded double quotes are escaped.

    /// let ascii = b_str!("Hello, \"BStr\"!");

    /// let s = CString::try_from_fmt(fmt!("{ascii:?}"))?;

    /// assert_eq!(s.as_bytes(), "\"Hello, \\\"BStr\\\"!\"".as_bytes());

    /// assert_eq!(s.to_bytes(), "\"Hello, \\\"BStr\\\"!\"".as_bytes());

    ///

    /// let non_ascii = b_str!("😺");

    /// let s = CString::try_from_fmt(fmt!("{non_ascii:?}"))?;

    /// assert_eq!(s.as_bytes(), "\"\\xf0\\x9f\\x98\\xba\"".as_bytes());

    /// assert_eq!(s.to_bytes(), "\"\\xf0\\x9f\\x98\\xba\"".as_bytes());

    /// # Ok::<(), kernel::error::Error>(())

    /// ```

    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -465,15 +465,15 @@ impl fmt::Display for CStr { 
    /// # use kernel::str::CString;

    /// let penguin = c_str!("🐧");

    /// let s = CString::try_from_fmt(fmt!("{penguin}"))?;

    /// assert_eq!(s.as_bytes_with_nul(), "\\xf0\\x9f\\x90\\xa7\0".as_bytes());

    /// assert_eq!(s.to_bytes_with_nul(), "\\xf0\\x9f\\x90\\xa7\0".as_bytes());

    ///

    /// let ascii = c_str!("so \"cool\"");

    /// let s = CString::try_from_fmt(fmt!("{ascii}"))?;

    /// assert_eq!(s.as_bytes_with_nul(), "so \"cool\"\0".as_bytes());

    /// assert_eq!(s.to_bytes_with_nul(), "so \"cool\"\0".as_bytes());

    /// # Ok::<(), kernel::error::Error>(())

    /// ```

    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

        for &c in self.as_bytes() {

        for &c in self.to_bytes() {

            if (0x20..0x7f).contains(&c) {

                // Printable character.

                f.write_char(c as char)?;
@@ -874,11 +874,11 @@ fn write_str(&mut self, s: &str) -> fmt::Result { 
/// use kernel::{str::CString, prelude::fmt};

///

/// let s = CString::try_from_fmt(fmt!("{}{}{}", "abc", 10, 20))?;

/// assert_eq!(s.as_bytes_with_nul(), "abc1020\0".as_bytes());

/// assert_eq!(s.to_bytes_with_nul(), "abc1020\0".as_bytes());

///

/// let tmp = "testing";

/// let s = CString::try_from_fmt(fmt!("{tmp}{}", 123))?;

/// assert_eq!(s.as_bytes_with_nul(), "testing123\0".as_bytes());

/// assert_eq!(s.to_bytes_with_nul(), "testing123\0".as_bytes());

///

/// // This fails because it has an embedded `NUL` byte.

/// let s = CString::try_from_fmt(fmt!("a\0b{}", 123));
@@ -948,7 +948,7 @@ impl<'a> TryFrom<&'a CStr> for CString { 
    fn try_from(cstr: &'a CStr) -> Result<CString, AllocError> {

        let mut buf = KVec::new();



        buf.extend_from_slice(cstr.as_bytes_with_nul(), GFP_KERNEL)?;

        buf.extend_from_slice(cstr.to_bytes_with_nul(), GFP_KERNEL)?;



        // INVARIANT: The `CStr` and `CString` types have the same invariants for

        // the string data, and we copied it over without changes.